William R. Keller
University of Maryland, Baltimore
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Featured researches published by William R. Keller.
Journal of Psychiatric Research | 2013
Gregory P. Strauss; William P. Horan; Brian Kirkpatrick; Bernard A. Fischer; William R. Keller; Pinar Miski; Robert W. Buchanan; Michael F. Green; William T. Carpenter
BACKGROUND Previous studies indicate that negative symptoms reflect a separable domain of pathology from other symptoms of schizophrenia. However, it is currently unclear whether negative symptoms themselves are multi-faceted, and whether sub-groups of patients who display unique negative symptom profiles can be identified. METHODS A data-driven approach was used to examine the heterogeneity of negative symptom presentations in two samples: Study 1 included 199 individuals with schizophrenia assessed with a standard measure of negative symptoms and Study 2 included 169 individuals meeting criteria for deficit schizophrenia (i.e., primary and enduring negative symptoms) assessed with a specialized measure of deficit symptoms. Cluster analysis was used to determine whether different groups of patients with distinct negative symptoms profiles could be identified. RESULTS Across both studies, we found evidence for two distinctive negative symptom sub-groups: one group with predominantly Avolition-Apathy (AA) symptoms and another with a predominantly Diminished Expression (DE) profile. Follow-up discriminant function analyses confirmed the validity of these groups. AA and DE negative symptom sub-groups significantly differed on clinically relevant external validators, including measures of functional outcome, premorbid adjustment, clinical course, disorganized symptoms, social cognition, sex, and ethnicity. CONCLUSIONS These results suggest that distinct subgroups of patients with elevated AA or DE can be identified within the broader diagnosis of schizophrenia and that these subgroups show clinically meaningful differences in presentation. Additionally, AA tends to be associated with poorer outcomes than DE, suggesting that it may be a more severe aspect of psychopathology.
Schizophrenia Research | 2012
Gregory P. Strauss; William R. Keller; Robert W. Buchanan; James M. Gold; Bernard A. Fischer; Robert P. McMahon; Lauren T. Catalano; Adam J. Culbreth; William T. Carpenter; Brian Kirkpatrick
The current study examined the psychometric properties of the Brief Negative Symptom Scale (BNSS), a next-generation rating instrument developed in response to the NIMH sponsored consensus development conference on negative symptoms. Participants included 100 individuals with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder who completed a clinical interview designed to assess negative, positive, disorganized, and general psychiatric symptoms, as well as functional outcome. A battery of anhedonia questionnaires and neuropsychological tests were also administered. Results indicated that the BNSS has excellent internal consistency and temporal stability, as well as good convergent and discriminant validity in its relationships with other symptom rating scales, functional outcome, self-reported anhedonia, and neuropsychological test scores. Given its brevity (13-items, 15-minute interview) and good psychometric characteristics, the BNSS can be considered a promising new instrument for use in clinical trials.
Schizophrenia Research | 2012
Gregory P. Strauss; L. Elliot Hong; James M. Gold; Robert W. Buchanan; Robert P. McMahon; William R. Keller; Bernard A. Fischer; Lauren T. Catalano; Adam J. Culbreth; William T. Carpenter; Brian Kirkpatrick
The current study examined the factor structure of the Brief Negative Symptom Scale (BNSS), a next-generation negative symptom rating instrument developed in response to the NIMH-sponsored Consensus Development Conference on Negative Symptoms. Participants included 146 individuals with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder. Principal axis factoring indicated two distinct factors explaining 68.7% of the variance. Similar to previous findings, the factors reflected motivation and pleasure and emotional expressivity. These findings provide further support for the construct validity of the BNSS, and for the existence of these two negative symptom factors.
Journal of Psychopharmacology | 2013
William R. Keller; Lionel M Kum; Maju Mathew Koola; Robert W. Buchanan; Deanna L. Kelly
Schizophrenia is a chronic debilitating mental disorder that affects about 1% of the US population. The pathophysiology and etiology remain unknown, thus new treatment targets have been challenging and few novel treatments with new mechanisms of action have come to market in the past few decades. Increasing attention has been paid to the role of inflammation in schizophrenia and new data suggests that decreasing inflammation and inflammatory biomarkers may play some role in schizophrenia treatment. This review summarizes the clinical trial literature regarding medications that possess anti-inflammatory properties that have been tested for schizophrenia symptoms and covers such medications as non-steroidal anti-inflammatory agents, such as the cyclo-oxygenase-2 (COX-2) inhibitors and aspirin, omega-3 fatty acids, neurosteroids and minocycline. Overall, there is accumulating evidence, albeit mostly adjunctive treatments, that agents working on inflammatory pathways have some benefits in people with schizophrenia. In the next few years the field will begin to see data on many treatments with anti-inflammatory properties that are currently under study. Hopefully advancements in understanding inflammation and effective treatments having anti-inflammatory properties may help revolutionize our understanding and provide new targets for prevention and treatment in schizophrenia.
Schizophrenia Research | 2012
Bernard A. Fischer; William R. Keller; Celso Arango; Godfrey D. Pearlson; Robert P. McMahon; Walter Meyer; Alan N. Francis; Brian Kirkpatrick; William T. Carpenter; Robert W. Buchanan
OBJECTIVE To examine the structural integrity of the dorsolateral prefrontal-basal ganglia-thalamocortical circuit in people with the deficit form of schizophrenia. METHOD A three-dimensional structural MRI sequence was used to conduct morphometric assessments of cortical and subcortical regions in deficit and nondeficit outpatients with schizophrenia and healthy controls. RESULTS The superior prefrontal and superior and middle temporal gyral gray matter volumes were significantly smaller in the deficit versus the nondeficit group and normal control groups. There were no significant group differences in examined subcortical structures. CONCLUSION People with deficit schizophrenia are characterized by selective reductions in the prefrontal and temporal cortex.
Journal of Clinical Psychopharmacology | 2015
Deanna L. Kelly; Kelli M. Sullivan; Joseph P. McEvoy; Robert P. McMahon; James M. Gold; Fang Liu; Dale Warfel; Gopal Vyas; Charles M. Richardson; Bernard A. Fischer; William R. Keller; Maju Mathew Koola; Stephanie Feldman; Jessica Russ; Richard S.E. Keefe; Jennifer Osing; Leeka Hubzin; Sharon August; Trina M. Walker; Robert W. Buchanan
Objective Clozapine is the most effective antipsychotic for treatment refractory people with schizophrenia, yet many patients only partially respond. Accumulating preclinical and clinical data suggest benefits with minocycline. We tested adjunct minocycline to clozapine in a 10-week, double-blind, placebo-controlled trial. Primary outcomes tested were positive, and cognitive symptoms, while avolition, anxiety/depression, and negative symptoms were secondary outcomes. Methods Schizophrenia and schizoaffective participants (n = 52) with persistent positive symptoms were randomized to receive adjunct minocycline (100 mg oral capsule twice daily; n = 29) or placebo (n = 23). Results Brief Psychiatric Rating Scale (BPRS) psychosis factor (P = 0.098; effect size [ES], 0.39) and BPRS total score (P = 0.075; ES, 0.55) were not significant. A change in total BPRS symptoms of more than or equal to 30% was observed in 7 (25%) of 28 among minocycline and 1 (4%) of 23 among placebo participants, respectively (P = 0.044). Global cognitive function (MATRICS Consensus Cognitive Battery) did not differ, although there was a significant variation in size of treatment effects among cognitive domains (P = 0.03), with significant improvement in working memory favoring minocycline (P = 0.023; ES, 0.41). The Scale for the Assessment of Negative Symptoms total score did not differ, but significant improvement in avolition with minocycline was noted (P = 0.012; ES, 0.34). Significant improvement in the BPRS anxiety/depression factor was observed with minocycline (P = 0.028; ES, 0.49). Minocycline was well tolerated with significantly fewer headaches and constipation compared with placebo. Conclusions Minocyclines effect on the MATRICS Consensus Cognitive Battery composite score and positive symptoms were not statistically significant. Significant improvements with minocycline were seen in working memory, avolition, and anxiety/depressive symptoms in a chronic population with persistent symptoms. Larger studies are needed to validate these findings.
CNS Neuroscience & Therapeutics | 2011
William R. Keller; Bernard A. Fischer; William T. Carpenter
Appropriate and reliable classification of mental illness is crucial for advancing the field of psychiatry as agreement on diagnosis has broad implications for treatment of mental disorders and research into the etiopathophysiology of mental disorders. Since schizophrenia was first recognized by Kraepelin (as dementia praecox), there has been much discussion about what does and does not diagnostically constitute the disorder. The importance placed upon different symptoms and course types associated with schizophrenia has been as heterogeneous as the disorder itself. This article focuses upon the classification of schizophrenia over the last 100 years, the current diagnosis of schizophrenia, changes for schizophrenia planned in the upcoming DSM 5, future directions for improving the diagnosis of schizophrenia, and the implications of a new diagnostic paradigm for the illness.
Schizophrenia Research | 2015
Gregory P. Strauss; William R. Keller; James I. Koenig; James M. Gold; Katherine H. Frost; Robert W. Buchanan
Lower endogenous levels of the neuropeptide oxytocin may be an important biological predictor of social cognition impairments in schizophrenia (SZ). Prior studies have demonstrated that lower-level social cognitive processes (e.g., facial affect perception) are significantly associated with reduced plasma oxytocin levels in SZ; however, it is unclear whether higher-level social cognition, which requires inferential processes and knowledge not directly presented in the stimulus, is associated with endogenous oxytocin. The current study explored the association between endogenous oxytocin levels and lower- and higher-level social cognition in 40 individuals diagnosed with SZ and 22 demographically matched healthy controls (CN). All participants received the Social Cue Recognition Test (SCRT), which presents participants with videotaped interpersonal vignettes and subsequent true/false questions related to concrete or abstract aspects of social interactions in the vignettes. Results indicated that SZ had significantly higher plasma oxytocin concentrations than CN. SZ and CN did not differ on SCRT hits, but SZ had more false positives and lower sensitivity scores than CN. Higher plasma oxytocin levels were associated with better sensitivity scores for abstract items in CN and fewer false positives for concrete items in individuals with SZ. Findings indicate that endogenous oxytocin levels predict accurate encoding of lower-level socially relevant information in SZ.
Schizophrenia Research | 2015
Gregory P. Strauss; William R. Keller; James I. Koenig; James M. Gold; Kathryn L. Ossenfort; Robert W. Buchanan
Basic neuroscience research provides strong evidence for the role of oxytocin in olfactory processes and social affiliation in rodents. Given prior indication of olfactory impairments that are linked to greater severity of asociality in schizophrenia, we examined the association between plasma oxytocin levels and measures of olfaction and social outcome in a sample of outpatients with schizophrenia (n=39) and demographically matched healthy controls (n=21). Participants completed the 40-item University of Pennsylvania Smell Identification Test (UPSIT), and rated each odor for how positive and how negative it made them feel. Results indicated that individuals with schizophrenia had higher plasma oxytocin levels and lower overall accuracy for UPSIT items than controls. Individuals with schizophrenia also reported experiencing more negative emotionality than controls in response to the olfactory stimuli. Lower plasma oxytocin levels were associated with poorer accuracy for pleasant and unpleasant odors and greater severity of asociality in individuals with schizophrenia. These findings suggest that endogenous oxytocin levels may be an important predictor of olfactory identification deficits and negative symptoms in schizophrenia.
BMC Psychiatry | 2013
Deanna L. Kelly; Amber Earl; Kelli M. Sullivan; Faith Dickerson; Stephanie Feldman; Robert P. McMahon; Robert W. Buchanan; Dale Warfel; William R. Keller; Bernard A. Fischer; Joo-Cheol Shim
Prolactin elevations occur in people treated with antipsychotic medications and are often much higher in women than in men. Hyperprolactinemia is known to cause amenorrhea, oligomenorrhea, galactorrhea and gynecomastia in females and is also associated with sexual dysfunction and bone loss. These side effects increase risk of antipsychotic nonadherence and suicide and pose significant problems in the long term management of women with schizophrenia. In this manuscript, we review the literature on prolactin; its physiology, plasma levels, side effects and strategies for treatment. We also present the rationale and protocol for an ongoing clinical trial to treat symptomatic hyperprolactinemia in premenopausal women with schizophrenia. More attention and focus are needed to address these significant side effects and help the field better personalize the treatment of women with schizophrenia.